This application claims the priority of European Patent Application Serial No. 01 810 319.2, filed Mar. 29, 2001, the subject matter of which is incorporated herein by reference.
The present invention relates, in general, to a surgical instrument, and more particularly to a surgical clamping instrument.
British Pat. No. 769,917 discloses a clamping instrument in the form of tweezers which includes two spaced-apart spring arms in parallel relationship. At their one end, the spring arms are connected to a spacer block, placed in-between the spring arms. A setting screw is provided to adjust the spring-elastic restoring force of the spring arms. At the other end, the spring arms are inwardly bent for detachable securement of jaws. Each spring arm further includes an arched pin which extends through a hole in the other spring arm and has a disk-like actuating member for moving the jaws apart to thereby allow grasping and holding of an object.
U.S. Pat. No. 4,844,065 discloses a clamping instrument in the form of a forceps for inserting a deformable intraocular lens. The clamping instrument has two elongate spring arms in crossing configuration, which are spaced from one another at their front end by a spacer and have angled ends to form jaws for grasping and holding the lens.
Other clamping instruments in the form of tweezers or forceps are known, for example, from U.S. Pat. Nos. 2,214,984 and 4,461,297. Their configuration is, however, very complicated and they are unsuitable for insertion and implanting a deformable lens into the eye of a living being.
Microsurgical procedures, in particular ophthalmologic surgical procedures increasingly demand instruments that are precise when it comes to grabbing an object while yet being easy to handle. Conventional instruments of this kind have shortcomings because the ophthalmologist is restricted in his or her mobility when, e.g., guiding an artificial lens to be implanted through an incision or to maintain an incised tissue flap manually in folded position to clear the surgical area.
It would therefore be desirable and advantageous to provide an improved surgical instrument, which obviates prior art shortcomings and ensures a precise handling during surgical procedures such as implanting an artificial lens or grasping an incised tissue part.
According to one aspect of the present invention, a surgical instrument, in particular ophthalmologic clamp, includes two spring arms disposed in substantial parallel relationship and interconnected on one end, two clamping elements, respectively connected to the other end of the spring arms, and an actuating mechanism for moving the spring arms relative to one another in opposition to a spring elastic restoring force of the spring arms to thereby implement an inverse movement of the clamping elements, wherein the actuating mechanism includes two plate-shaped operating members in parallel disposition to the spring arms, and four pins, with two pins disposed in spaced-apart relationship in longitudinal direction and having one end connected to one of the operating members and another end operatively connected to a confronting one of the spring arms, and two pins disposed in spaced-apart relationship in longitudinal direction and having one end connected to the other one of the operating members and another end operatively connected to other one of the spring arms.
The present invention resolves prior art problems by so arranging the spaced-apart pins that each of the pins extends between an operating member and a distal one of the spring arms so as to ensure a precise opening and closing of the clamping elements relative to one another.
According to another feature of the present invention, the actuating mechanism may be so configured that a movement path of the clamping elements into an opening direction is determined by a distance that the operating members can move into abutment with the spring arms. Suitably, the spring arms may each have an indentation for receiving the operating members, when the operating members are press together.
According to another feature of the present invention, the operating members may have a roughened outer surface and received in the indentations of the spring arms except for the roughened outer surface.